07-30-11: AlmargI should have mentioned in this statement that prior to performing the speed measurement I had re-formatted the drive into multiple partitions, using Windows XP, which defeats the alignment the drive was originally supplied with, and supposedly makes it necessary to use the WD alignment utility. But no speed compromise resulted, even though I didn't use the utility.
I'll add that I recently installed an external (USB) Western Digital advanced format drive on a Windows XP system, without using the alignment utility, and its speed as measured with HD Tune was as good as I would expect from any USB-connected drive.
Regards,
-- Al